Calls have been made for a major review of rules which allow waste to be dumped at sea after palm oil was washed up on Southwold's beach for the second time in as many months.

The plea has been made by Waveney MP Peter Aldous following the latest discovery of solidified palm oil at Southwold, where the yellow waxy balls of grease surfaced four weeks ago and again at the weekend.

Mr Aldous wants to see a change in regulations that allow shipping companies to legally dump the tank cleaning solution outside the 12-mile reach of Britain's territorial waters.

Although the dark yellow substance is not thought to be harmful to humans, some dogs have fallen ill after coming into contact with it. Meanwhile, taxpayers are footing the bill for the waste to be safely removed and disposed of.

Stephen Ardley, head of green environment at Waveney District Council, said: 'I'm disgusted that this continues to happen. It's totally unacceptable. Whoever chooses to do this should have to pay for the clean-up.

'In all of these cases it's the council that gets the blame. I'm frustrated and angered that these shipping companies can not be pursued.'

Mr Aldous spoke to the Maritime and Coastguard Agency (MCA) following a similar discovery in October in the area and was told that the ship responsible had been about 70 miles out to sea.

He said: 'I was told what they were doing was legal.

'The MCA told me it happens throughout the world and that it would require international agreement to be stopped.

'It has been a particular problem in the Low Countries and I am informed that the Dutch government is to put forward a report to the international community. I have written to our minister asking for this government to have regard for that report.

'This is taking place outside national waters, so we need international agreement to make a change.'

Last year, Westminster voted in favour of moving all UK ship-to-ship oil transfers to a designated zone 12 miles off Southwold.

The Southwold and Reydon Society fought the proposals and has declared its concern over the dumping of palm oil.

Michael Rowan-Robinson, chairman, said: 'It is highly irritating that whichever shipping company is discharging this stuff is getting away with it.

'A big issue recently was ship-to-ship oil transfers. Although we can't see the tankers over the horizon, the issue remains a concern.'

Society secretary John Perkins added: 'This is very disturbing news. Although we believe it is palm oil, our contention is that it could be far worse with oil tankers operating nearby.

'There is a high level of concern about any waste thrown into the sea and washed up on our beaches. The whole economy of the area is based mainly around the seafront.'

Simon Tobin, mayor of Southwold, said: 'The town council would like complete clarification on this situation. The information we have been getting is very grey. We need a solid answer on where this substance is coming from – and we want it stopping as soon as possible.'

An MCA spokesman said ships are permitted to offload a small amount of residue upon completion of tank washing, and under strictly controlled conditions, including that it takes place no less than 12 nautical miles from the nearest land, in a depth of water no less than 25 metres.